Abstract: In a compact combined spray drying and after-treatment apparatus having internal gas filters and an internal fluidized bed in the drying chamber and a fluidized bed in the after-treatment zone, pipe means are used for conducting a stream of particle-loaded gas formed in the after-treatment zone to suitable locations in the drying chamber without disturbing the normal operation of the drying chamber and the fluidized bed therein.

Abstract: A moist non-rewetted particulate material obtained from an extract of e.g. coffee by drying, is subjected to a heat treatment being carried out without affecting the moisture content of the particulate material at a combination of temperature and time being adequate for effecting fusion so as to form a compact cake-like structure, which is disintegrated into granular material before drying to final moisture content, whereby fines may be separated without being subjected to final drying, and recirculated in the process. Hereby a product having an appearance similar to and a quality comparable to or better than that of freeze dried coffee can be obtained in a less expensive manner.

Abstract: In a spray drying process utilizing a spray dryer having internal gas filters and an internal fluidized bed and comprising an after-treatment of the product in a separate unit outside the spray drying chamber, which treatment produces a particle-loaded gas stream, said particle-loaded gas stream is conducted from the separate unit to the spray drying chamber. The stream passes, together with the spent drying gas in the drying chamber, the filters integrated in said chamber. Several plant modifications are suggested for performing the process which involves substantial savings by making external particle collectors superfluous.